Hemodynamics of intrahepatic portal vein studied in healthy subjects and liver cirrhosis by pulsed Doppler method

Abstract

The hemodynamics of the intrahepatic portal vein in 35 healthy subjects and 74 patients with liver cirrhosis was studied by measuring blood flow velocity with pulsed Doppler ultrasound technique. The flow velocity of portal vein decreased from the portal trunk to the first branches and to the second branches in the right and left lobes. Especially, an abrupt decrease of the flow velocity in the umbilical part of the left portal vein was characteristic of hemodynamics in the intrahepatic portal vein. Theflow velocity in the third branches decreased more than that of the second branch in the right portalvein, but did not exist in the left. And the velocity was almost equal in all the subsegments. Blood clots of the left portal vein in 25 of 36 lesions were found in 31 patients with intrahepatic portal vein thrombus. This characteristic hemodynamics of the left portal vein was thought to be the main cause for the formation of blood clots. In the group with liver cirrhosis, the flow velocity was lower than in healthy subjects in the portal trunk, bilateral first branches and right second branches, but did not exist in the left second branch and bilateral third branches. No interrelationship between the intrahepatic portal flow velocity and the severity of liver cirrhosis and portal hypertension was observed.